Part I: Changes in Food and Drink
How We Eat

Our Diet and Our Microbiome

Just consider what these food villains are doing to your gut:

So, which foods are good for your gut?
The first step in gut-friendly eating is to fill your beneficial bacteria’s pantry shelves with their favorite snacks. Your gut bacteria are fond of the polyphenols found in plant foods like fruits and vegetables. But what they like best are foods high in prebiotic fiber, such as bananas, beans, lentils, oats, barley, onions, leeks, garlic, apples, and asparagus.[14]
Once your gut bacteria have chowed down on prebiotic fiber, they get busy building your gut architecture — specifically, the protective mucus layer of your gut barrier. And that helps keep inflammation at a healthy level throughout your body.[15]
You can also introduce new beneficial bacteria (or probiotics) to your gut by eating fermented foods. Kefir, yogurt, and kimchi are among the most concentrated sources of friendly flora, but sauerkraut, kombucha, and miso contain some, too.[16]
Just remember — if your gut architecture isn’t healthy, any probiotics you introduce to your system probably won’t stick around. So just eating fermented foods or taking probiotics on its own typically isn’t enough to turn your gut health around.
Animal and test tube studies have shown that eating protein from peas and mung beans can improve the ratio of beneficial to harmful bacteria in the gut.[17,18] If that effect holds true for plant protein in general, eating more tofu, tempeh, lentils, and chickpeas is a smart move.
Bonus: beans and pulses contain fiber, so they also support your gut architecture by ensuring good bacteria eat their favorite food instead of your gut mucus layer.
Fats aren’t all bad for your gut. In addition to being good for your heart, your brain, and your eyes, the omega-3 fats found in fatty fish, flaxseed, and walnuts also appear to be good for your gut bacteria.[19]
Mouse studies have shown that mice eating a fish oil-enriched diet have higher levels of good bacteria such as Bifidobacterium and Lactobacillus compared to mice eating lard-derived fats.
How We Drink

Take a look at the impact of these drinks on your gut:

So, how should you change your drinking habits to support gut health?
For optimal gut health, limit your consumption of sugary drinks. The World Health Organization recommends adults and children reduce their daily intake of free sugars to less than 10% of their total energy intake, or about 50 grams (12 teaspoons) per day.[29]
It notes that a further reduction to 5% per day would provide additional health benefits.
If you want to drink, go for the alcoholic beverage that may provide a gut boost: red wine. Limit hard alcohol to that special occasion when you want a fancy cocktail on a night out.
Whether chlorinated water disrupts our gut microbiota is still an open question, but so far the evidence points that way. Countertop water filters are inexpensive. Investing in one could provide you with peace of mind.
Key Take-Aways
- Common habits of contemporary life endanger our gut architecture, starting with what we eat and drink.
- Hunter-gatherer cultures, who eat a lot of fiber, have much more gut microbial diversity than Westernized societies. This kind of diet also promotes healthier gut architecture — the actual anatomy of the gut.
- Saturated and trans fats, refined carbohydrates, sugar, and artificial sweeteners reduce beneficial gut bacteria populations, negatively alter the composition of the gut microbiota, and inflame gut architecture.
- Gut-friendly foods include prebiotic fiber (found in certain fruits, veggies, grains and beans), fermented foods, plant protein, and omega-3 fatty acids.
- Sugary drinks, alcohol, and chlorinated water can lower bacterial diversity, cause dysbiosis, and damage gut architecture.
- Limiting sugary drinks and switching to red wine may preserve gut health, and investing in a water filter can eliminate chlorine from your drinking water.

References
- http://nautil.us/issue/30/identity/how-the-western-diet-has-derailed-our-evolution
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5083795/
- https://www.ncbi.nlm.nih.gov/pubmed/30655101
- https://www.ncbi.nlm.nih.gov/pubmed/30120538
- https://www.healthline.com/health-news/can-a-high-fat-diet-change-your-microbiome
- https://gut.bmj.com/content/68/8/1417
- https://www.shape.com/weight-loss/tips-plans/one-factor-might-be-standing-way-your-weight-loss
- https://www.pbs.org/wgbh/nova/article/sugar-keeps-good-microbes-at-bay/
- https://www.sciencedaily.com/releases/2019/11/191114115949.htm
- https://www.firstforwomen.com/posts/diet/dr-oz-veggie-flush-smoothie-173878
- https://www.ncbi.nlm.nih.gov/pubmed/25231862
- https://www.ncbi.nlm.nih.gov/pubmed/27090230
- https://www.ncbi.nlm.nih.gov/pubmed/29975731
- https://www.genuinehealth.com/en-us/genuine-hub/why-gut-health-matters-and-how-to-eat-your-way-to-a-healthier-gut/
- https://www.healthline.com/health/food-nutrition/fiber-diet-good-for-gut-and-health#the-scientific-lowdown-on-fiber
- https://www.cleaneatingmag.com/clean-diet/best-fermented-foods-for-gut-health
- https://www.ncbi.nlm.nih.gov/pubmed/29777704
- https://www.ncbi.nlm.nih.gov/pubmed/21276631
- https://www.ncbi.nlm.nih.gov/pubmed/29793999
- https://www.cbsnews.com/news/coffee-wine-good-for-the-gut-but-what-about-soda/
- https://www.pnas.org/content/101/51/17593
- https://www.sciencedaily.com/releases/2014/05/140512155025.htm
- https://www.healthline.com/nutrition/8-things-that-harm-gut-bacteria#section4
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3362077/
- https://www.ncbi.nlm.nih.gov/pubmed/22552027
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5513683/
- https://www.motherjones.com/environment/2014/08/case-against-chlorinated-tap-water/
- https://www.mdpi.com/2078-1547/10/1/10
- https://www.who.int/mediacentre/news/releases/2015/sugar-guideline/en/